plucky (3) gsignal.3.gz

NAME

       gsignal, ssignal - software signal facility

LIBRARY

       Standard C library (libc, -lc)

SYNOPSIS

       #include <signal.h>

       typedef void (*sighandler_t)(int);

       [[deprecated]] int gsignal(int signum);

       [[deprecated]] sighandler_t ssignal(int signum, sighandler_t action);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       gsignal(), ssignal():
           Since glibc 2.19:
               _DEFAULT_SOURCE
           glibc 2.19 and earlier:
               _SVID_SOURCE

DESCRIPTION

       Don't  use  these  functions  under  Linux.  Due to a historical mistake, under Linux these functions are
       aliases for raise(3) and signal(2), respectively.

       Elsewhere, on System V-like systems, these functions implement software signaling,  entirely  independent
       of the classical signal(2) and kill(2) functions.  The function ssignal() defines the action to take when
       the software signal with number signum is raised using the function gsignal(), and returns  the  previous
       such  action or SIG_DFL.  The function gsignal() does the following: if no action (or the action SIG_DFL)
       was specified for signum, then it does nothing and returns 0.  If the action SIG_IGN  was  specified  for
       signum,  then  it  does  nothing and returns 1.  Otherwise, it resets the action to SIG_DFL and calls the
       action function with argument signum, and returns the value returned by  that  function.   The  range  of
       possible values signum varies (often 1–15 or 1–17).

ATTRIBUTES

       For an explanation of the terms used in this section, see attributes(7).

       ┌──────────────────────────────────────────────────────────────────────┬───────────────┬─────────────────┐
       │Interface                                                             │ Attribute     │ Value           │
       ├──────────────────────────────────────────────────────────────────────┼───────────────┼─────────────────┤
       │gsignal()                                                             │ Thread safety │ MT-Safe         │
       ├──────────────────────────────────────────────────────────────────────┼───────────────┼─────────────────┤
       │ssignal()                                                             │ Thread safety │ MT-Safe sigintr │
       └──────────────────────────────────────────────────────────────────────┴───────────────┴─────────────────┘

STANDARDS

       None.

HISTORY

       AIX,  DG/UX,  HP-UX,  SCO, Solaris, Tru64.  They are called obsolete under most of these systems, and are
       broken under glibc.  Some systems also have gsignal_r() and ssignal_r().

SEE ALSO

       kill(2), signal(2), raise(3)